The Tissue Procurement Core will organize the retrieval of human tissues for RCOB research. specimens of human oral mucosa will be obtained from the clinics of the Departments of Periodontics and Oral Surgery. Tissues removed during routine treatment for periodontal diseases include variously inflamed human gingiva and granulation tissue. In addition, specimens of normal human oral mucosa and periodontal ligament which adhere to extracted teeth will be obtained. Samples of venous blood and of gingival crevicular fluid will be obtained from consenting patients as needed. Pertinent patient information will be collected from existing records and supplied to investigators as needed. The core faculty and staff will interact closely with, and serve as a liaison between, RCOB investigators and the faculty and staff of the Departments of Oral Surgery and Periodontics. The Core will also interact closely with the General Tissue Procurement Facility on campus operated by the Department of Pathology and the Comprehensive Cancer Center.